Publications by authors named "Aloys Tijsma"

We recently published a preliminary assessment of the activity of a poly (ADP-ribose) polymerase (PARP) inhibitor, stenoparib, also known as 2X-121, which inhibits viral replication by affecting pathways of the host. Here we show that stenoparib effectively inhibits a SARS-CoV-2 wild type (BavPat1/2020) strain and four additional variant strains; alpha (B.1.

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The SARS-CoV-2 variant is rapidly spreading across the world and causes to resurge infections. We previously reported that CT-P59 presented its in vivo potency against Beta variants, despite its reduced activity in cell experiments. Yet, it remains uncertain to exert the antiviral effect of CT-P59 on Gamma, Delta and its associated variants (L452R).

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The global circulation of newly emerging variants of SARS-CoV-2 is a new threat to public health due to their increased transmissibility and immune evasion. Moreover, currently available vaccines and therapeutic antibodies were shown to be less effective against new variants, in particular, the South African (SA) variant, termed 501Y.V2 or B.

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Contamination of bivalve molluscs with viruses is well recognized as a food safety risk. A microbiological criterion for norovirus (NoV) and hepatitis A virus (HAV) in shellfish, however, does not exist in the European Union currently. The aim of this study was to evaluate the contamination levels of these viruses for fluctuation over a long period (2013-2017) in oyster (n = 266) and mussel samples (n = 490) using a method based on ISO/TS 15216-1: 2013.

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Enterovirus A71 (EV-A71) is one of the main causative agents of hand-foot-and-mouth disease and is occasionally associated with severe neurological complications. EV-A71 pathophysiology is poorly understood due to the lack of small animal models that robustly support viral replication in relevant organs/tissues. Here, we show that adult severe combined immune-deficient (SCID) mice can serve as an EV-A71 infection model to study neurotropic determinants and viral tropism.

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Background: Salmonella spp are a major cause of food-borne outbreaks in Europe. We investigated a large multi-country outbreak of Salmonella enterica serotype Enteritidis in the EU and European Economic Area (EEA).

Methods: A confirmed case was defined as a laboratory-confirmed infection with the outbreak strains of S Enteritidis based on whole-genome sequencing (WGS), occurring between May 1, 2015, and Oct 31, 2018.

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The aim of the present study was to assess pork liver and meat products present on the Dutch market for the presence of hepatitis E virus (HEV) RNA. HEV RNA was detected in 27.3% of 521 products sampled from Dutch retail stores in 2016.

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The aim of the present study was to investigate whether the use of porcine blood(products) in food could be a risk for a hepatitis E virus (HEV) infection. HEV RNA was detected in 33/36 batches of (non-heated) liquid products and in 7/24 spray dried powder products. Contamination levels varied among the products, but were highest in liquid whole blood, plasma and fibrinogen reaching levels of 2.

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It has been generally accepted that hydantoin [5-(3,4-dichlorophenyl)methylhydantoin] exerts its anti-enterovirus activity by solely inhibiting viral assembly. However, we here show that hydantoin inhibits enteroviral RNA synthesis as well as subgenomic replication in a dose-dependent manner. We demonstrate that inhibition of RNA synthesis is the predominant mechanism of action at relatively high concentrations of hydantoin.

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The Global Polio Eradication Initiative, launched in 1988, had as its goal the eradication of polio worldwide by the year 2000 through large-scale vaccinations campaigns with the live attenuated oral PV vaccine (OPV) (Griffiths et al., Biologicals 34:73-74, 2006). Despite substantial progress, polio remains endemic in several countries and new imported cases are reported on a regular basis ( http://www.

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Very recently, we demonstrated that N(6)-isopentenyladenosine, a cytokinin nucleoside, exerts a potent and selective antiviral effect on the replication of human enterovirus 71. The present study is devoted to the structure optimization of another natural compound: N(6)-benzyladenosine. We mainly focused on the exploration of the size and nature of the linker between the adenine and the phenyl ring, as well as on the necessity of the D-ribose residue.

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The replication of enterovirus 71 (EV71) and coxsackievirus A16 (CVA16), which are the major cause of hand, foot and mouth disease (HFMD) in children, can be inhibited by the capsid binder GPP3. Here, we present the crystal structure of CVA16 in complex with GPP3, which clarifies the role of the key residues involved in interactions with the inhibitor. Based on this model, in silico docking was performed to investigate the interactions with the two next-generation capsid binders NLD and ALD, which we show to be potent inhibitors of a panel of enteroviruses with potentially interesting pharmacological properties.

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Aims: Viral myocarditis (VM) is an important cause of heart failure and sudden cardiac death in young healthy adults; it is also an aetiological precursor of dilated cardiomyopathy. We explored the role of the miR-221/-222 family that is up-regulated in VM.

Methods And Results: Here, we show that microRNA-221 (miR-221) and miR-222 levels are significantly elevated during acute VM caused by Coxsackievirus B3 (CVB3).

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In this study, we demonstrate that N(6)-isopentenyladenosine, which essentially is a plant cytokinin-like compound, exerts a potent and selective antiviral effect on the replication of human enterovirus 71 with an EC50 of 1.0 ± 0.2 μM and a selectivity index (SI) of 5.

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Antivirals against enterovirus 71 (EV71) are urgently needed. We demonstrate that the novel enteroviral protease inhibitor (PI) SG85 and capsid binder (CB) vapendavir efficiently inhibit the in vitro replication of 21 EV71 strains/isolates that are representative of the different genogroups A, B, and C. The PI rupintrivir, the CB pirodavir, and the host-targeting compound enviroxime, which were included as reference compounds, also inhibited the replication of all isolates.

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A novel small molecule, H1PVAT, was identified as a potent and selective inhibitor of the in vitro replication of all three poliovirus serotypes, whereas no activity was observed against other enteroviruses. Time-of-drug-addition studies revealed that the compound interfered with an early stage of virus replication. Four independently-selected H1PVAT-resistant virus variants uniformly carried the single amino acid substitution I194F in the VP1 capsid protein.

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